Bordeaux, France

Recovering lost heat from an incineration plant

The Bordeaux waste-to-energy plant produces electricity and heat from waste. In this type of steam cycle, the condenser accounts for 50 to 60% of heat losses: recovering this heat significantly improves the plant's overall efficiency.

Two BROAD absorption heat pumps recover heat from the condenser water at around 40 °C. They run on 6 bar(g) steam extracted from the turbine and preheat the return water of the Bordeaux metropolitan district heating network (Saint-Jean Belcier district), where demand is growing.

• Unit type: single-effect steam absorption heat pump × 2 units
• Heating capacity: up to 11 MW in total (adjustable from 1.4 to 11 MW)
• Heat source: 6 bar(g) steam extracted from the turbine
• Heat recovered: up to 4.6 MW from the condenser water (inlet 40 °C, outlet 35 °C)
• Heating water: district heating network, up to 84 °C at the outlet
• Heating COP: up to 1.70
• Use: district heating
• System: a booster heat exchanger raises the water to 100 °C and takes over when the heat pumps are not running